The overall goals of the Flow Cytometry Core Facility are to provide state- of-the-art flow cytometry and cell sorting capabilities to assist both in ongoing research and in developmental projects related to arthritis and musculoskeletal diseases. The specific objectives are: 1. To provide flow cytometry with ultraviolet and multi-color immunofluorescent capabilities for arthritis and musculoskeletal diseases investigators 2. To stimulate new users and new applications of flow cytometry and cell sorting 3. To work with the New York Hospital-Cornell University Medical College (NYH-CUMC) flow facility to achieve a coordinated and complementary capability